Related papers: "Counterpart" method for abundance determinations …
The CHemical Abundances of Spirals (CHAOS) project leverages the combined power of the Large Binocular Telescope (LBT) with the broad spectral range and sensitivity of the Multi Object Double Spectrograph (MODS) to measure "direct"…
We present an adapted version of the code HII-CHI-Mistry-UV (P\'erez-Montero & Amor\'in 2017) to derive chemical abundances from emission lines in the ultraviolet, for use in narrow line regions (NLR) of Active Galactic Nuclei (AGN). We…
We present long-slit spectrophotometric observations in the red and near infrared of 12 HII galaxies. The spectral range includes the sulphur lines [SII] at wavelengths 6716, 6731 angstroms and [SIII] at 6312 angstroms and 9069, 9532…
We have carried out the largest and most unbiased search for hypercompact (HC) HII regions. Our method combines four interferometric radio continuum surveys (THOR, CORNISH, MAGPIS and White2005) with far-infrared and sub-mm Galactic Plane…
Context. The knowledge of abundance distributions is central to understanding the formation and evolution of galaxies. Most of the relations employed for the derivation of gas abundances have so far been derived from observations of outer…
(Abridged) We reassess the alpha-element abundance ratios (Ne/O, S/O, Ar/O) with respect to metallicity in ~1000 spectra of Galactic and extragalactic HII regions and star-forming galaxies (SFGs) of the local Universe. Using the DEep…
HII regions are the ionized spheres surrounding high-mass stars. They are ideal targets for tracing Galactic structure because they are predominantly found in spiral arms and have high luminosities at infrared and radio wavelengths. In the…
We discuss the accuracy of the abundance determinations of H II regions in our Galaxy and other galaxies. We focus on the main observational constraints derived from abundance determinations that have implications for models of galactic…
We use a sample of 37 H II regions with high quality spectra to study the behavior of the relative abundances of several elements as a function of metallicity. The sample includes spectra for eight H II regions of the Magellanic Clouds,…
We describe a new method for determining total gas-phase abundances for the Galactic ISM with minimal ionization uncertainties. For sight lines toward globular clusters containing both UV-bright stars and radio pulsars, one can measure…
We present a catalog of $\sim$52,000 extragalactic HII regions and their spectroscopic properties obtained using Integral Field Spectroscopy (IFS) from MUSE observations. The sample analyzed in this study contains 678 galaxies within the…
This Letter presents a new, remarkably simple diagnostic specifically designed to derive chemical abundances for high redshift galaxies. It uses only the H \alpha, [N II] and [S II] emission lines, which can usually be observed in a single…
We aim at deriving the molecular abundances and temperatures of the hot molecular cores in the high-mass star-forming region NGC 6334I and consequently deriving their physical and astrochemical conditions. In the framework of the Herschel…
Observing giant HII regions at fine spatial scales uncovers detailed structures and reveals variations in ionization, abundance, and dynamical properties of ionized gas and the effect of stellar feedback. Using emission line data of M33…
We have obtained deep optical, long-slit spectrophotometry of the Galactic HII regions M 17, NGC 3576 and of the Magellanic Cloud HII regions 30 Doradus, LMC N11B and SMC N66, recording the optical recombination lines (ORLs) of CII, NII and…
We have compared Monte Carlo photoionization models of H II regions with a uniform density distribution with models with the same central stars and chemical compositions but with 3-D hierarchical clumps. We compare the abundances of He, N,…
Aims: By performing a detailed radiative transfer analysis, we determine fractional abundances of circumstellar H2O in the envelopes around six M-type asymptotic giant branch stars. The models are also used to predict H2O spectral line…
Based on high quality observations of multiplet V1 of OII and the NLTE atomic computations of OII we study the density and temperature of a sample of HII regions. We find that the signature for oxygen rich clumps of high density and low…
The HII region oxygen abundance is a key observable for studying chemical properties of galaxies. Deriving oxygen abundances using optical spectra often relies on empirical strong-line calibrations calibrated to the direct method. Existing…
The accepted explanation of the observed dichotomy of two orders of magnitude between in situ measurements of electron density in HII regions, derived from emission line ratios, and average measurements based on integrated emission measure,…